Delta Pulse

[kt315]

Treiti informs us that he did order and gotta PSB's for DP, you can see a some his result, an all-in-process. I hope as he is here so can add anything he has yet attained.

[jcm05]

Hello,

Beautiful work.
It will be interesting to compare performances following the same protocol.

If there are of improvements to bring to improve the performance I will be very interested.

JCM

[Satel]

Hi everyone!

I made Delta Pulse and it find 2cm coin in 18cm in air and metal case with diameter 10cm in 32 cm in air.I read forum about Delta Pulse and understand, that this distances is little shortly. I made some changes in schematic, but nothing helps.My coil diameter is 16,5 cm, 2,08 mH, 3,9ohms.I tryd a coil from Hammerhead, but nothing helps.Can somebody give exactly description, what changes must to do in shematic and what coil parameters must be, that Delta Pulse works correctly.
Thanks and good luck to all

[Geo]

Hi everyone!

I made Delta Pulse and it find 2cm coin in 18cm in air and metal case with diameter 10cm in 32 cm in air.I read forum about Delta Pulse and understand, that this distances is little shortly. I made some changes in schematic, but nothing helps.My coil diameter is 16,5 cm, 2,08 mH, 3,9ohms.I tryd a coil from Hammerhead, but nothing helps.Can somebody give exactly description, what changes must to do in shematic and what coil parameters must be, that Delta Pulse works correctly.
Thanks and good luck to all

Hi. The inductance must be between 350 and 500 uH with resistor bigger than 1.5..2 Ohm. Try 22..28 turns with wire 0.5mm and diameter 25 cm.
You must detect the 2cm coin at 25 cm about.
Good luck.

[Satel]

Thanks Geo!

Can You tell me, in Delta Pulse schematic, transistor T8, it must be n-p-n or p-n-p.I see XR71 schematic and there it was p-n-p.

Thanks

[Geo]

Thanks Geo!

Can You tell me, in Delta Pulse schematic, transistor T8, it must be n-p-n or p-n-p.I see XR71 schematic and there it was p-n-p.

Thanks

Yes (npn). This is a small difference between Delta and XR71. XR71 use TL072 at D5 (IC5).

[okantex]

Hi Kt315

I tried to build pcb for delta.but it was full of cracks and cuts.
I wonder about treiti's board.is it made by two sided copper board or with another tecnique.first picture looks like made by electrolitic dyes.
and second problem was mounting (sockets,legs ...what do we call the part that we put under IC s.to protect them from soldering heat.

[okantex]

sorry I forget to add problem.

it is that soldering this units legs on front side of board.they kiss board well that I can not solder it.

[ivconic]

HI


Hi KT315,
I made delta pulse 4-5 years ago and it didn't work at all. These days
i made it again, respecting your hints and it is working just fine!
Concerning all mentioned here i found out that i miss connection
between 2.pin and 6. pin on the NE555. I guess that was the main reason
it didn't work in the past. Now it is working. I made up a 42 cm coil,
with 35 windings, 0.7 wire gauge. Resistance of a coil is 7,1 ohm.
I noticed that under the 4,5 ohm, my IRF640 is getting hot, very hot!
I replaced it with IRF730 and it is much better now. IRF730 is cool on
5, 6, and 7,1 ohm's. I made a several different coils, with diff. sizes,
diff.number of windings and resistances. But this 42 cm coil is working
better than others. I tried mentioned coil on 20cm with 30 windings 0.35mm
wire, but IRF is hot and detection is very poor. I simply can not beleive
that anybody gained mentioned results with this coil. The dumper resistor is
2K2. When replaced with 1K, the same thing!!!
One more thing, i can adjust freq. from 115 Hz up to 650 Hz. The best results
are on 398 Hz, so far.
Now results:
1l paint can ..... 85cm
PC case...........130cm
1cm coin.......... 22cm
2cm coin.......... 27cm
kitchen knife..... 42cm
etc.
I didn't try on cola can...these days i'll find some and try it.
But you mentioned some 70cm on cola can.According to that i think
that your dp is working much better than mine!?WIth which coil?
What is the catch?
If you can help me on that...I might made some mistake...
The 45cm Pulstar II coil resistance is 1.9 ohm. If i connect it on
my Delta Pulse, i guess IRF will blow in a minute! Can you explain me
can I readjust something in DP and connect lower resistance coils on it?
regards!
P.S.
I like this DP, it is very stabile and looks pretty.
But there is no extra tone. When detection is on, you can hear nice
tone which pitching up as you put object closer to coil.But when you
remove object, tone decay at once. I would like some extra tone or even
some kind of weak noise, as i used to hear on Pulsestar II.This is because
sometimes i can pass over object faster and not detect it at all!
Is there any chance to achieve that?

[ivconic]

No echoes yet...


Nobody interested yet?
I replaced dumper 2k2 with 1k/1w just for testing.Results are even better for 5-10% almost. Instead all TL062 i put TL072,instead LF357 i put LF356(simply i do not have those) and all works fine.Power consumption is:
without detection 70ma
with full detection 110ma
Results:

1l paint can .....over 90cm
pc case ..........over 140cm
1cm coin..........28cm
2cm coin..........35cm

all test in the air, of course.....i am waiting to buy a suitable case,to pack
device in it amd than go outdoor and test it again...
bue!

[Geo]

Nobody interested yet?
I replaced dumper 2k2 with 1k/1w just for testing.Results are even better for 5-10% almost. Instead all TL062 i put TL072,instead LF357 i put LF356(simply i do not have those) and all works fine.Power consumption is:
without detection 70ma
with full detection 110ma
Results:

1l paint can .....over 90cm
pc case ..........over 140cm
1cm coin..........28cm
2cm coin..........35cm

all test in the air, of course.....i am waiting to buy a suitable case,to pack
device in it amd than go outdoor and test it again...
bue!

Hi Ivconic. This time i am very busy so i can not answer to you or to do experiment with my XR71. The second results are good and better than mine. If you have free time you can do some experiments and to tell the results.
1. Change R21 with 200k to increase the gain 4 times.
2. Change R17 with 270k to increase the gain 2.25 times.
3. With an extra pcb you can change LF357 (or 356) and connect a 5534 with current offset and larger R17 (1Mohm is ok).
If all changes work then the DP will be a very very sensitive detector.
Btw who is the inductance of the 42 cm coil?

regards

[ivconic]

Geo, hi !


I busted out my impendance meter a few months ago, so i can not tell you that, but it has 35 windings, 0.7mm Cul wire...
One more thing....yesterday i made another coil, on "hoola hop" toy with diamm. 75cm (round shape) i made 18 windings, 1mm wire, 4.4 ohms, and it is working crazy!!! That paint can(1 liter) it can detetct over 140cm, i did'nt test other objects cose it was performed inside my workshop and coil is detecting almost everything from every directions!!!I had to lower the gain at the minimum to perform that test with the can,otherwise it "beep"-ing all the time.I still can not
test it outdoor cose i did'nt put it in the box yet. But the "reset" knob is working
perfect and once you push it device is calming at once.
Thanks for those tips.I am gonna try a.s.a.p. and report here.
I just do not know about increasing the gain, is it safe now with this performances already? And what about power consumption.It will increase also.
But anyway i'll try it...
Geo, my friend thank's and regards!!!

[ivconic]

Large coil

75cm hhop coil...

[Geo]

I busted out my impendance meter a few months ago, so i can not tell you that, but it has 35 windings, 0.7mm Cul wire...
One more thing....yesterday i made another coil, on "hoola hop" toy with diamm. 75cm (round shape) i made 18 windings, 1mm wire, 4.4 ohms, and it is working crazy!!! That paint can(1 liter) it can detetct over 140cm, i did'nt test other objects cose it was performed inside my workshop and coil is detecting almost everything from every directions!!!I had to lower the gain at the minimum to perform that test with the can,otherwise it "beep"-ing all the time.Geo, my friend thank's and regards!!!

Hi Ivconic. At First congratulation for the very good coil. Did you tried the 75 cm coil with less turns? If required 18 turns then at 25 cm coil require at least 40 turns. With 75 cm coil can you detect a 2..3 cm coin? If yes then it is a big coil for small and for big objects. The dumping resistor was 2k2 or 1Kohm?
If you put the frequency at 100 hz then at who distance can you detect the 1 litre can?
Thanks a lot
Regerds

[Geo]

Hi Ivcinic again. I do a calculate for your coils and something do not like at me.
If the calculations are good then the 42 cm (16.8 in) coil has an inductance of about 1mH and the 75 cm coil (29.3 in) has an inductance about 500 uH. What are you say? Who is the better inductance for DeltaPulse? Can you add some turns at the 75 cm coil to see how it work?

Regards